EMPLOYEE STOCK BENEFIT PLANS Share-based Payment Arrangement, Cost by Plan (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Share-based Payment Arrangement, Expense	$ 213	$ 48	$ 423	$ 101
Share-based Payment Arrangement, Expense, Tax Benefit	40	9	86	19
Proceeds and Excess Tax Benefit from Share-based Compensation	5		28
Cost of products sold [Member]
Share-based Payment Arrangement, Expense	9	3	19	7
Marketing, selling and administrative [Member]
Share-based Payment Arrangement, Expense	86	28	174	58
Research and development [Member]
Share-based Payment Arrangement, Expense	89	17	183	36
Other (Income)/expense, net [Member]
Share-based Payment Arrangement, Expense	29	$ 0	47	$ 0
Celgene [Member]
Share-based Payment Arrangement, Expense	98		221
Share-based Payment Arrangement, Accelerated Cost	$ 29		47
Celgene [Member] \| Celgene Contingent Value Rights [Member]
Share-based Payment Arrangement, Expense			$ 9

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5047-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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The aggregate cash inflow comprised of the amount received from (a) employees to acquire the entity's shares under incentive awards, including stock option exercises and restricted stock arrangements, and (b) the excess tax benefit arising from such transactions.

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Amount of additional cost recognized for award under share-based payment arrangement from occurrence of event accelerating recognition of cost.

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